This invention relates to catheters.
An embryo transfer catheter is used to transport an embryo from a location where the embryo was fertilised to the woman in whom the embryo is to be transferred. One end of the catheter is inserted in the uterus and the embryo is expelled from the catheter to the uterus. The embryo is fertilised and grown under carefully controlled conditions in a culture medium, in particular, care is taken to keep the embryo at the correct temperature to encourage its growth. Although the embryo in the catheter is transported as quickly as possible, there can often be delays in transferring the embryo to the patient. In particular, if the position of the uterus is found to be difficult, the surgeon may need to undertake additional procedures before the catheter can be inserted. This can delay insertion of the embryo and may cause its temperature to drop while the catheter is exposed to room temperature. Similar problems arise with oocyte recovery catheters used to transfer oocytes from a woman for in vitro fertilisation or other treatment.